Acteoside Isolated from Colebrookea oppositifolia Smith Attenuates Epilepsy in Mice Via Modulation of Gamma-Aminobutyric Acid Pathways

Medicinal plants for epileptic seizures: Phytoconstituents, pharmacology and mechanisms revisited

ETHNOPHARMACOLOGICAL RELEVANCE

Epilepsy is a neurological disorder that presents with recurring and spontaneous seizures. It is prevalent worldwide, affecting up to 65 million people, with 80% of cases found in lower-income countries. Medicinal plants are commonly employed for managing and treating epilepsy and convulsions due to their unique therapeutic properties. With increasing research and clinical application, medicinal plants are gaining attention globally due to their potent therapeutic effects and fewer side effects. The development of new plant-based antiepileptic/anticonvulsant agents has become a major focus in the pharmaceutical industry.

AIM OF THE REVIEW

This article summarizes recent research on medicinal plants with reported antiepileptic/anticonvulsant effects. It provides pharmacological and molecular mechanism of action information for the crude extracts and related active constituents evaluated in preclinical research for the treatment of epilepsy and convulsions, and offers a reference for the development of future related studies in this area.

MATERIALS AND METHODS

Articles related to ethnopharmacological and antiepileptic studies on plants or natural products from 2018 to 2023 were collected from PubMed, Web of Science and Scopus, etc. using keywords related to epilepsy, medicinal plants, and natural products, etc. RESULTS: Eighty plant species are commonly used to treat epilepsy and convulsions in African and Asian countries. Sixty natural products showing potential for antiepileptic/anticonvulsant effects have been identified from these medicinal plants. These products can be broadly classified as alkaloids, coumarins, flavonoids, saponins, terpenoids and other compounds. The antiepileptic action of plant extracts and their active ingredients can be classified according to their abilities to modulate the GABAergic and glutamatergic systems, act as antioxidants, exhibit anti-neuroinflammatory effects, and provide neuroprotection. In addition, we highlight that some medicinal plants capable of pharmacologically relieving epilepsy and cognition may be therapeutically useful in the treatment of refractory epilepsy.

CONCLUSIONS

The review highlights the fact that herbal medicinal products used in traditional medicine are a valuable source of potential candidates for antiepileptic drugs. This confirms and encourages the antiepileptic/anticonvulsant activity of certain medicinal plants, which could serve as inspiration for further development. However, the aspects of structural modification and optimization, metabolism, toxicology, mechanisms, and clinical trials are not fully understood and need to be further explored.

Pre-existing Toxoplasma gondii infection increases susceptibility to pentylenetetrazol-induced seizures independent of traumatic brain injury in mice

Introduction

Post-traumatic epilepsy (PTE) is a debilitating chronic outcome of traumatic brain injury (TBI), and neuroinflammation is implicated in increased seizure susceptibility and epileptogenesis. However, how common clinical factors, such as infection, may modify neuroinflammation and PTE development has been understudied. The neurotropic parasite, Toxoplasma gondii (T. gondii) incurably infects one-third of the world's population. Thus, many TBI patients have a pre-existing T. gondii infection at the time of injury. T. gondii infection results in chronic low-grade inflammation and altered signaling pathways within the brain, and preliminary clinical evidence suggest that it may be a risk factor for epilepsy. Despite this, no studies have considered how a pre-existing T. gondii infection may alter the development of PTE.

Methods

This study aimed to provide insight into this knowledge gap by assessing how a pre-existing T. gondii infection alters susceptibility to, and severity of, pentylenetetrazol (PTZ)-induced seizures (i.e., a surrogate marker of epileptogenesis/PTE) at a chronic stage of TBI recovery. We hypothesized that T. gondii will increase the likelihood and severity of seizures following PTZ administration, and that this would occur in the presence of intensified neuroinflammation. To test this, 6-week old male and female C57BL/6 Jax mice were intraperitoneally injected with 50,000 T. gondii tachyzoites or with the PBS vehicle only. At 12-weeks old, mice either received a severe TBI via controlled cortical impact or sham injury. At 18-weeks post-injury, mice were administered 40 mg/kg PTZ and video-recorded for evaluation of seizure susceptibility. Fresh cortical tissue was then collected for gene expression analyses.

Results

Although no synergistic effects were evident between infection and TBI, chronic T. gondii infection alone had robust effects on the PTZ-seizure response and gene expression of markers related to inflammatory, oxidative stress, and glutamatergic pathways. In addition to this, females were more susceptible to PTZ-induced seizures than males. While TBI did not impact PTZ responses, injury effects were evident at the molecular level.

Discussion

Our data suggests that a pre-existing T. gondii infection is an important modifier of seizure susceptibility independent of brain injury, and considerable attention should be directed toward delineating the mechanisms underlying this pro-epileptogenic factor.

The pharmacokinetic property and pharmacological activity of acteoside: A review

Acteoside (AC), a phenylpropanoid glycoside isolated from many dicotyledonous plants, has been demonstrated various pharmacological activities, including anti-oxidation, anti-inflammation, anti-cancer, neuroprotection, cardiovascular protection, anti-diabetes, bone and cartilage protection, hepatoprotection, and anti-microorganism. However, AC has a poor bioavailability, which can be potentially improved by different strategies. The health-promoting characteristics of AC can be attributed to its mediation in many signaling pathways, such as MAPK, NF-κB, PI3K/AKT, TGFβ/Smad, and AMPK/mTOR. Interestingly, docking simulation study indicates that AC can be an effective candidate to inhibit the activity of SARS-CoV2 main protease and protect against COVID-19. Many clinical trials for AC have been investigated, and it shows great potentials in drug development.

Anticancer effects of acteoside: Mechanistic insights and therapeutic status

Cancer, the uncontrolled proliferation and metastasis of abnormal cells, is a major public health issue worldwide. To date, several natural compounds have been reported with their efficacy in the treatment of different types of cancer. Chemotherapeutic agents are used in cancer treatment and prevention, among other aspects. Acteoside is a phenylethanoid glycoside, first isolated from Verbascum sinuatum, which has demonstrated multiple effects, including antioxidant, anti-epileptic, neuroprotective, anti-inflammatory, antifungal, antihypertensive, and anti-leishmanial properties. This review gathered, analyzed, and summarized the literature on acteoside and its anticancer properties. All the available information about this compound and its role in different types of cancer was collected using different scientific search engines, including PubMed, Scopus, Springer Link, Wiley Online, Web of Science, Scifinder, ScienceDirect, and Google Scholar. Acteoside is found in a variety of plants and has been shown to have anticancer activity in many experimental models through oxidative stress, apoptosis, anti-angiogenesis, anti-invasion, anti-metastasis, synergism with other agents, and anti-proliferative effects through modulation of several pathways. In conclusion, acteoside exhibited potent anticancer activity against different cancer cell lines through modulating several cancer signaling pathways in different non- and pre-clinical experimental models and thus could be a strong candidate for further clinical studies.

Investigation of 1, 3, 4 Oxadiazole Derivative in PTZ-Induced Neurodegeneration: A Simulation and Molecular Approach

Objective

The study investigated the effect 5-[(naphthalen-2-yloxy) methyl]-1,3,4-oxadiaszole2-thiol (B3) in animal model of acute epileptic shock.

Methods

The pharmacokinetics profile of B3 was checked through SwissADME software. The binding affinities of B3, diazepam, and flumazenil (FLZ) were obtained through Auto Dock and PyRx. Post docking analysis and interpretation of hydrogen bonds were performed through Discovery Studio Visualizer 2016. Molecular dynamics simulations of three complexes were carried out through Desmond software package. B3 was then proceeded in PTZ-induced acute seizures models. Flumazenil was used in animal studies for elucidation of possible mechanism of B3. After behavioral studies, the animals were sacrificed, and the brain samples were isolated and stored in 4% formalin for molecular investigations including H and E staining, IHC staining and Elisa etc.

Results

The results demonstrate that B3 at 20 and 40 mg/kg prolonged the onset time of generalized seizures. B3 considerably increased the expression of protective glutathione S-transferase and glutathione reductase and reduced lipid peroxidation and inducible nitric oxide synthase (P < 0.001) in the cortex. B3 significantly suppressed (P < 0.01) the over expression of the inflammatory mediator tumor necrosis factor–α, whose up-regulation is reported in acute epileptic shocks.

Conclusion

Hence, it is concluded from the aforementioned results that B3 provides neuroprotective effects PTZ-induced acute epileptic model. FLZ pretreatment resulted in inhibition of the anticonvulsant effect of B3. B3 possesses anticonvulsant effect which may be mediated through GABA_A mediated antiepileptic pathway.

Acteoside isolated from Colebrookea oppositifolia attenuates I/R brain injury in Wistar rats via modulation of HIF-1α, NF-κB, and VEGF pathways

AIMS

The objective of this study was to assess the anti-stroke activity of acteoside isolated from methanolic root extract of C. oppositifolia METHODS: Ischemia-reperfusion(I/R) brain injury was induced in Wistar rats to assess the anti-stroke activity of acteoside. Rats were pretreated with acteoside (10, 25 & 50 mg/kg, p.o.) before the induction of I/R injury. Parameters such as neurological, motor-cognitive functions were evaluated along with morphological (brain volume, infarct size), biochemical (SOD, Catalase, GSH, lipid peroxidation, TNF-α, IL-6, IL-10, ICAM-1, HIF-1α, VEGF, and NF-κB), histopathological, and gene expression studies (HIF-1α, VEGF) were performed to study the protective effect of acteoside against I/R induced brain injury.

RESULTS

I/R injury caused significant deterioration of neurological (p < 0.01), motor (p < 0.01) and cognitive (p < 0.01) functions, associated with increase in the brain volume (p < 0.01), and infarct size (p < 0.01); increase in the levels of MDA, TNF-α, IL-6, ICAM-1, HIF-1α, VEGF, and NF-κB along with significant decrease in SOD, catalase, GSH, and IL-10 (p < 0.01 for all parameters) compared to Sham control group. Histology of brain tissue of disease control group exhibited significant vascular changes, neutrophil infiltration, cerebral oedema, and necrosis of the neuronal cells. Further, the gene-expression studies showed significant increase in the HIF-1α (p < 0.01) and VEGF (p < 0.01) mRNA levels in the I/R control compared to Sham control. Interestingly, the acteoside (10, 25 & 50 mg/kg) has prevented the neurological, motor and cognitive dysfunctions, along with inhibiting the morphological, biochemical, histological and gene expression changes induced by I/R-injury (p < 0.05 for 10 mg; p < 0.01 for 25 & 50 mg/kg of acteoside for all the parameters).

CONCLUSION

These findings suggest that acteoside possess potent anti-stroke activity through modulation of HIF-1α, NF-κB, and VEGF pathway along with its potent antioxidant activity.